Search results for "Multidimensional data"
showing 10 items of 10 documents
Table Compression
2016
Data Compression Techniques for massive tables are described. Related methodological results are also presented.
Multidimensional financial development, exporter behavior and export diversification
2020
Financial development shapes export sector performance because exporters need external finance and face credit constraints. Previous empirical research has relied largely on single-country studies. The Exporter Dynamics Database (EDD), which features firm-level exports from over 60 countries, reveals differences in the microstructure of the export sector across countries. In this paper, we first provide new evidence that these differences are related to cross-country variation in financial development and structure. Second, we combine the EDD and multidimensional data on financial development with a global database on export diversification. This study is the first to examine how macrolevel…
Principal components for multivariate spatiotemporal functional data
2014
Multivariate spatio-temporal data consist of a three way array with two dimensions’ domains both structured, temporally and spatially; think for example to a set of different pollutant levels recorded for a month/year at different sites. In this kind of dataset we can recognize time series along one dimension, spatial series along another and multivariate data along the third dimension. Statistical techniques aiming at handling huge amounts of information are very important in this context and classical dimension reduction techniques, such as Principal Components, are relevant, allowing to compress the information without much loss. Although time series, as well as spatial series, are recor…
On the Road to Accurate Biomarkers for Cardiometabolic Diseases by Integrating Precision and Gender Medicine Approaches
2019
The need to facilitate the complex management of cardiometabolic diseases (CMD) has led to the detection of many biomarkers, however, there are no clear explanations of their role in the prevention, diagnosis or prognosis of these diseases. Molecules associated with disease pathways represent valid disease surrogates and well-fitted CMD biomarkers. To address this challenge, data from multi-omics types (genomics, epigenomics, transcriptomics, proteomics, metabolomics, microbiomics, and nutrigenomics), from human and animal models, have become available. However, individual omics types only provide data on a small part of molecules involved in the complex CMD mechanisms, whereas, here, we pr…
Changes in the flow and quality of water in the dam reservoir of the Mała Panew catchment (South Poland) characterized by multidimensional data analys…
2023
Multidimensional exploratory techniques, such as the Principal Component Analysis (PCA), have been used to analyze long-term changes in the fl ow regime and quality of water of the lowland dam reservoir Turawa (south-west Poland) in the catchment of the Mała Panew river (a tributary of the Odra). The paper proves that during the period of 1998–2016 the Turawa reservoir was equalizing the river’s water fl ow. Moreover, various physicochemical water quality indicators were analyzed at three measurement points (at the tributary’s mouth into the reservoir, in the reservoir itself and at the outfl ow from the reservoir). The water quality assessment was performed by analyzing physicochemical ind…
Greedy and K-Greedy algoritmhs for multidimensional data association
2011
[EN] The multidimensional assignment (MDA) problem is a combinatorial optimization problem arising in many applications, for instance multitarget tracking (MTT). The objective of an MDA problem of dimension $d\in\Bbb{N}$ is to match groups of $d$ objects in such a way that each measurement is associated with at most one track and each track is associated with at most one measurement from each list, optimizing a certain objective function. It is well known that the MDA problem is NP-hard for $d\geq3$. In this paper five new polynomial time heuristics to solve the MDA problem arising in MTT are presented. They are all based on the semi-greedy approach introduced in earlier research. Experimen…
Visual Data Mining With Self-organizing Maps for “Self-monitoring” Data Analysis
2016
Data collected in psychological studies are mainly characterized by containing a large number of variables (multidimensional data sets). Analyzing multidimensional data can be a difficult task, especially if only classical approaches are used (hypothesis tests, analyses of variance, linear models, etc.). Regarding multidimensional models, visual techniques play an important role because they can show the relationships among variables in a data set. Parallel coordinates and Chernoff faces are good examples of this. This article presents self-organizing maps (SOM), a multivariate visual data mining technique used to provide global visualizations of all the data. This technique is presented as…
Local Splines on Non-uniform Grid
2018
In this Chapter and in the next Chap. 7, we deal with continuous rather than discrete and discrete-time splines. In these and only these chapters, we abandon the assumption that the grid, on which the splines are constructed, is uniform and consider splines on arbitrary grids. Two types of local cubic and quadratic splines on non-uniform grids are described: 1. The simplest variation-diminishing splines and 2. The quasi-interpolating splines. The splines are computed by simple fast computational algorithms that utilize relations between the splines and interpolation polynomials. In addition, these relations provide sharp estimations of splines’ approximation accuracy. These splines can serv…
Application of Electronic Nose for Evaluation of Wastewater Treatment Process Effects at Full-Scale WWTP
2019
This paper presents the results of studies aiming at the assessment and classification of wastewater using an electronic nose. During the experiment, an attempt was made to classify the medium based on an analysis of signals from a gas sensor array, the intensity of which depended on the levels of volatile compounds in the headspace gas mixture above the wastewater table. The research involved samples collected from the mechanical and biological treatment devices of a full-scale wastewater treatment plant (WWTP), as well as wastewater analysis. The measurements were carried out with a metal-oxide-semiconductor (MOS) gas sensor array, when coupled with a computing unit (e.g., a computer with…
Creación de ocasiones de gol en fútbol de élite. Diferencias tácticas entre Real Madrid CF y FC Barcelona (Creating goal scoring opportunities in eli…
2017
El objetivo de este estudio fue comparar los indicadores tácticos utilizados en la creación de ocasiones de gol entre Real Madrid C.F. (RMCF) y F.C. Barcelona (FCB). Todas las posesiones finalizadas en ocasión de gol (n=945) durante 64 partidos (32 por equipo) de la Liga BBVA 2011-2012 fueron analizadas a través de observación sistemática. Las posesiones fueron agrupadas según el tipo de inicio en “recuperaciones” (n=526), “reanudaciones” (n=199), y “acciones a balón parado” (n=175). 9 dimensiones relacionadas con indicadores tácticos fueron analizadas utilizando análisis chicuadrado. En recuperaciones, RMCF registro más penetración inicial (p<0.01), mayor porcentaje de contraataques (p&…